I'm currently using Mood, based on a recommendation in this sub. It's not bad, has some good animations and highly customizable right down to the nitty gritty.
However, Texta is my main app, also for speed and customizations.

Been using textra pro for the a while then switched to the Samsung messaging app for Gear capabilities. Might switch back to textra to see if I'm missing anything, but Samsung messenger isn't bad at all.

That should factor into your choice when buying a phone then. If you strongly dislike voice assistants why buy a phone that comes with two? If you dislike them why is disabling remapping the key not enough for you? (Or even better installing a custom rom that doesn't have voice assistants.) What's the point of your post other than to complain?

edit:

P.S. I get there's ways to disable Bixby but that's not what this is about.

Nice downvotes, please explain why what I posted above doesn't add to conversation or how its wrong. I thought the point of buying Android was to have more control of your phone? Simply unlock it and do what you want to customize your device. I already gave alternatives below.

The S8 doesn't give you the option to disable the Bixby button on the side of the phone. It's right below the volume buttons. If you accidentally hit it, it launches Bixby home and it's annoying.
They should at least give you a choice, and they don't.
Also, if you want to disable it, you need to jump through hoops to do it. I disabled mine, but I had to start a developer account and get keys blah blah blah. Most people won't be willing to do this.

You can remap that key to another functionality or to Google voice if you prefer that. However, that still doesn't detract from my original point. If you hate Voice Assistants factor that in to your purchasing preferences. Get a phone that supports copperheadOS so you don't have to deal with them ever again.